反应详情

The preferred aldehyde for the second route is benzaldehyde, especially when the glycol is ethylene glycol and the N-halogenated imide is N-bromosuccinimide. More specifically, 2-phenyl-1,3-dioxolane can be prepared by mixing benzaldehyde and ethylene glycol in a 1.0 to 1.2 mol ratio in an organic solvent containing a catalytic amount of an organic acid, such as p-toluenesulfonic acid. The mixture is heated and allowed to reflux for about an hour and a half, then treated with potassium carbonate, filtered, and distilled to produce 2-phenyl-1,3-dioxolane. The dioxolane is subsequently dissolved in carbon tetrachloride with an equimolar amount of N-bromosuccinimide and a catalytic amount of benzoyl peroxide. After heating under reflux conditions for up to 16 hours, cooling, and filtering, the mixture produces a filtrate that can be further concentrated to yield an ester, 2-bromoethyl benzoate. The ester so produced is used as an alkylating agent when reacted with a tertiary amine yielding a quaternary ammonium salt.

1. temperatureAfter heating under reflux conditions for up to 16 hours
2. temperaturecooling
3. filtrationfiltering
4. customthe mixture produces a filtrate that
5. concentrationcan be further concentrated